fonts/verifyhexfont.cpp

   1 #include <cstdint>
   2 #include <cstdlib>
   3 #include <iostream>
   4 #include <set>
   5
   6 extern uint32_t fontdata_size;
   7 extern uint32_t fontdata[];
   8
   9 uint32_t mdir_use = 0;
  10 uint32_t mdir_nuse = 0;
  11 uint32_t sdir_gkey = 0;
  12 uint32_t sdir_bkey = 0;
  13 uint32_t ftype0 = 0;
  14 uint32_t ftype1 = 0;
  15 std::set<uint32_t> seen;
  16
  17 //This is Jenkin's MIX function.
  18 uint32_t keyhash(uint32_t key, uint32_t item, uint32_t mod)
  19 {
  20         uint32_t a = key;
  21         uint32_t b = 0;
  22         uint32_t c = item;
  23         a=a-b;  a=a-c;  a=a^(c >> 13);
  24         b=b-c;  b=b-a;  b=b^(a << 8);
  25         c=c-a;  c=c-b;  c=c^(b >> 13);
  26         a=a-b;  a=a-c;  a=a^(c >> 12);
  27         b=b-c;  b=b-a;  b=b^(a << 16);
  28         c=c-a;  c=c-b;  c=c^(b >> 5);
  29         a=a-b;  a=a-c;  a=a^(c >> 3);
  30         b=b-c;  b=b-a;  b=b^(a << 10);
  31         c=c-a;  c=c-b;  c=c^(b >> 15);
  32         return c % mod;
  33 }
  34
  35 void verify_font(uint32_t cp, uint32_t offset)
  36 {
  37         if(offset >= fontdata_size) {
  38                 std::cerr << "Font verify error: Bad offset for codepoint " << cp << "." << std::endl;
  39         }
  40         if(seen.count(offset))
  41                 return;
  42         if(fontdata[offset] > 1) {
  43                 std::cerr << "Font verify error: Bad glyph type for codepoint " << cp << "." << std::endl;
  44                 exit(1);
  45         }
  46         if(fontdata[offset] == 0)
  47                 ftype0++;
  48         else if(fontdata[offset] == 1)
  49                 ftype1++;
  50         seen.insert(offset);
  51 }
  52
  53 void verify_subdirectory(uint32_t offset, uint32_t mseed, uint32_t msize, uint32_t snum)
  54 {
  55         if(offset + 2 > fontdata_size) {
  56                 std::cerr << "Font verify error: Subdirectory offset out of range: " << offset << "." << std::endl;
  57                 exit(1);
  58         }
  59         uint32_t sseed = fontdata[offset++];
  60         uint32_t ssize = fontdata[offset++];
  61         if(offset + 2 * ssize > fontdata_size) {
  62                 std::cerr << "Font verify error: Subdirectory offset out of range: " << offset - 2 << "." << std::endl;
  63                 exit(1);
  64         }
  65         if(ssize)
  66                 mdir_use++;
  67         else
  68                 mdir_nuse++;
  69         for(uint32_t i = 0; i < ssize; i++) {
  70                 uint32_t cp = fontdata[offset++];
  71                 uint32_t foffset = fontdata[offset++];
  72                 if(keyhash(mseed, cp, msize) == snum && keyhash(sseed, cp, ssize) == i) {
  73                         verify_font(cp, foffset);
  74                         sdir_gkey++;
  75                 } else if(foffset != 0) {
  76                         std::cerr << "Font verify error: Bad codepoint with nonzero offset: " << i << " of "
  77                                 << snum << "." << std::endl;
  78                         exit(1);
  79                 } else
  80                         sdir_bkey++;
  81         }
  82 }
  83
  84 void verify_main_directory(uint32_t offset)
  85 {
  86         if(offset + 2 > fontdata_size) {
  87                 std::cerr << "Font verify error: Main directory offset out of range: " << offset << "." << std::endl;
  88                 exit(1);
  89         }
  90         uint32_t mseed = fontdata[offset++];
  91         uint32_t msize = fontdata[offset++];
  92         if(offset + msize > fontdata_size) {
  93                 std::cerr << "Font verify error: Main directory offset out of range: " << offset - 2 << "."
  94                         << std::endl;
  95                 exit(1);
  96         }
  97         for(uint32_t i = 0; i < msize; i++)
  98                 verify_subdirectory(fontdata[offset++], mseed, msize, i);
  99 }
 100
 101 int main()
 102 {
 103         if(fontdata_size == 0) {
 104                 std::cerr << "Font verify error: Empty fontdata." << std::endl;
 105                 exit(1);
 106         }
 107         verify_main_directory(fontdata[0]);
 108         std::cerr << "Font verify successful!" << std::endl;
 109         std::cerr << "Main directory entries: " << (mdir_use + mdir_nuse) << " (" << mdir_use << " used + "
 110                 << mdir_nuse << " not_used)." << std::endl;
 111         std::cerr << "Subdirectory entries:  " << (sdir_gkey + sdir_bkey) << " (" << sdir_gkey << " good + "
 112                 << sdir_bkey << " bad)." << std::endl;
 113         std::cerr << "Distinct glyphs:       " << (ftype0 + ftype1) << " (" << ftype0 << " narrow + "
 114                 << ftype1 << " wide)." << std::endl;
 115         return 0;
 116 }